redesign and reimplement proxy config service and tracker, revise proxy ui on cros

chrome/browser/net/pref_proxy_config_tracker.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_NET_PREF_PROXY_CONFIG_SERVICE_H_
-#define CHROME_BROWSER_NET_PREF_PROXY_CONFIG_SERVICE_H_
+#ifndef CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_H_
+#define CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "chrome/browser/prefs/proxy_config_dictionary.h"
 #include "content/common/notification_observer.h"
 #include "net/proxy/proxy_config.h"
 #include "net/proxy/proxy_config_service.h"
 
 class PrefService;
 class PrefSetObserver;
 
-// A helper class that tracks proxy preferences. It translates the configuration
-// to net::ProxyConfig and proxies the result over to the IO thread for
-// PrefProxyConfigService to use.
-class PrefProxyConfigTracker
-    : public base::RefCountedThreadSafe<PrefProxyConfigTracker>,
-      public NotificationObserver {
- public:
-  // Observer interface used to send out notifications on the IO thread about
-  // changes to the proxy configuration.
-  class Observer {
-   public:
-    virtual ~Observer() {}
-    virtual void OnPrefProxyConfigChanged() = 0;
-  };
-
-  // Return codes for GetProxyConfig.
-  enum ConfigState {
-    // Configuration is valid and present.
-    CONFIG_PRESENT,
-    // There is a fallback configuration present.
-    CONFIG_FALLBACK,
-    // Configuration is known to be not set.
-    CONFIG_UNSET,
-  };
-
-  explicit PrefProxyConfigTracker(PrefService* pref_service);
-
-  // Observer manipulation is only valid on the IO thread.
-  void AddObserver(Observer* observer);
-  void RemoveObserver(Observer* observer);
-
-  // Get the proxy configuration currently defined by preferences. Status is
-  // indicated in the return value. Writes the configuration to |config| unless
-  // the return value is CONFIG_UNSET, in which case |config| is not touched.
-  ConfigState GetProxyConfig(net::ProxyConfig* config);
-
-  // Notifies the tracker that the pref service passed upon construction is
-  // about to go away. This must be called from the UI thread.
-  void DetachFromPrefService();
-
- private:
-  friend class base::RefCountedThreadSafe<PrefProxyConfigTracker>;
-  virtual ~PrefProxyConfigTracker();
-
-  // NotificationObserver implementation:
-  virtual void Observe(int type,
-                       const NotificationSource& source,
-                       const NotificationDetails& details);
-
-  // Install a new configuration. This is invoked on the IO thread to update
-  // the internal state after handling a pref change on the UI thread.
-  // |config_state| indicates the new state we're switching to, and |config| is
-  // the new preference-based proxy configuration if |config_state| is different
-  // from CONFIG_UNSET.
-  void InstallProxyConfig(const net::ProxyConfig& config, ConfigState state);
-
-  // Creates a proxy configuration from proxy-related preferences. Configuration
-  // is stored in |config| and the return value indicates whether the
-  // configuration is valid.
-  ConfigState ReadPrefConfig(net::ProxyConfig* config);
-
-  // Converts a ProxyConfigDictionary to net::ProxyConfig representation.
-  // Returns true if the data from in the dictionary is valid, false otherwise.
-  static bool PrefConfigToNetConfig(const ProxyConfigDictionary& proxy_dict,
-                                    net::ProxyConfig* config);
-
-  // Configuration as defined by prefs. Only to be accessed from the IO thread
-  // (except for construction).
-  net::ProxyConfig pref_config_;
-
-  // Tracks configuration state. |pref_config_| is valid only if |config_state_|
-  // is not CONFIG_UNSET.
-  ConfigState config_state_;
-
-  // List of observers, accessed exclusively from the IO thread.
-  ObserverList<Observer, true> observers_;
-
-  // Pref-related members that should only be accessed from the UI thread.
-  PrefService* pref_service_;
-  scoped_ptr<PrefSetObserver> proxy_prefs_observer_;
-
-  DISALLOW_COPY_AND_ASSIGN(PrefProxyConfigTracker);
-};
-
 // A net::ProxyConfigService implementation that applies preference proxy
-// settings as overrides to the proxy configuration determined by a baseline
-// delegate ProxyConfigService.
-class PrefProxyConfigService
+// settings (pushed from PrefProxyConfigTracker) as overrides to the proxy
+// configuration determined by a baseline delegate ProxyConfigService on
+// non-ChromeOS platforms. ChromeOS has its own implementation of overrides in
+// chromeos::ProxyConfigServiceImpl.
+class ChromeProxyConfigService
     : public net::ProxyConfigService,
-      public net::ProxyConfigService::Observer,
-      public PrefProxyConfigTracker::Observer {
+      public net::ProxyConfigService::Observer {
  public:
   // Takes ownership of the passed |base_service|.
-  PrefProxyConfigService(PrefProxyConfigTracker* tracker,
-                         net::ProxyConfigService* base_service);
-  virtual ~PrefProxyConfigService();
+  explicit ChromeProxyConfigService(net::ProxyConfigService* base_service);
+  virtual ~ChromeProxyConfigService();
 
   // ProxyConfigService implementation:
   virtual void AddObserver(net::ProxyConfigService::Observer* observer);
   virtual void RemoveObserver(net::ProxyConfigService::Observer* observer);
   virtual ConfigAvailability GetLatestProxyConfig(net::ProxyConfig* config);
   virtual void OnLazyPoll();
 
-  static void RegisterPrefs(PrefService* user_prefs);
+  // Method on IO thread that receives the preference proxy settings pushed from
+  // PrefProxyConfigTracker.
+  void UpdateProxyConfig(ProxyPrefs::ConfigState config_state,
+                         const net::ProxyConfig& config);
 
  private:
   // ProxyConfigService::Observer implementation:
   virtual void OnProxyConfigChanged(const net::ProxyConfig& config,
                                     ConfigAvailability availability);
 
-  // PrefProxyConfigTracker::Observer implementation:
-  virtual void OnPrefProxyConfigChanged();
-
-  // Makes sure that the observer registrations with the base service and the
-  // tracker object are set up.
-  void RegisterObservers();
+  // Makes sure that the observer registration with the base service is set up.
+  void RegisterObserver();
 
   scoped_ptr<net::ProxyConfigService> base_service_;
   ObserverList<net::ProxyConfigService::Observer, true> observers_;
-  scoped_refptr<PrefProxyConfigTracker> pref_config_tracker_;
 
-  // Indicates whether the base service and tracker registrations are done.
-  bool registered_observers_;
+  // Tracks configuration state of |pref_config_|. |pref_config_| is valid only
+  // if |pref_config_state_| is not CONFIG_UNSET.
+  ProxyPrefs::ConfigState pref_config_state_;
 
-  DISALLOW_COPY_AND_ASSIGN(PrefProxyConfigService);
+  // Configuration as defined by prefs.
+  net::ProxyConfig pref_config_;
+
+  // Indicates whether the base service registration is done.
+  bool registered_observer_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeProxyConfigService);
 };
 
-#endif  // CHROME_BROWSER_NET_PREF_PROXY_CONFIG_SERVICE_H_
+// A class that tracks proxy preferences. It translates the configuration
+// to net::ProxyConfig and pushes the result over to the IO thread for
+// ChromeProxyConfigService::UpdateProxyConfig to use.
+class PrefProxyConfigTracker : public NotificationObserver {
+ public:
+  explicit PrefProxyConfigTracker(PrefService* pref_service);
+  virtual ~PrefProxyConfigTracker();
+
+  // Sets the proxy config service to push the preference proxy to.
+  void SetChromeProxyConfigService(
+      ChromeProxyConfigService* proxy_config_service);
+
+  // Notifies the tracker that the pref service passed upon construction is
+  // about to go away. This must be called from the UI thread.
+  void DetachFromPrefService();
+
+  // Determines if |config_state| takes precedence regardless, which happens if
+  // config is from policy or extension or other-precede.
+  static bool PrefPrecedes(ProxyPrefs::ConfigState config_state);
+
+  // Determines the proxy configuration that should take effect in the network
+  // layer, based on prefs and system configurations.
+  // |pref_state| refers to state of |pref_config|.
+  // |system_availability| refers to availability of |system_config|.
+  // |ignore_fallback_config| indicates if fallback config from prefs should
+  // be ignored.
+  // Returns effective |effective_config| and its state in
+  // |effective_config_source|.
+  static net::ProxyConfigService::ConfigAvailability GetEffectiveProxyConfig(
+      ProxyPrefs::ConfigState pref_state,
+      const net::ProxyConfig& pref_config,
+      net::ProxyConfigService::ConfigAvailability system_availability,
+      const net::ProxyConfig& system_config,
+      bool ignore_fallback_config,
+      ProxyPrefs::ConfigState* effective_config_state,
+      net::ProxyConfig* effective_config);
+
+  // Registers the preferene proxy.
+  static void RegisterPrefs(PrefService* user_prefs);
+
+ protected:
+  // Get the proxy configuration currently defined by preferences.
+  // Status is indicated in the return value.
+  // Writes the configuration to |config| unless the return value is
+  // CONFIG_UNSET, in which case |config| and |config_source| are not touched.
+  ProxyPrefs::ConfigState GetProxyConfig(net::ProxyConfig* config);
+
+  // Called when there's a change in prefs proxy config.
+  // Subclasses can extend it for changes in other sources of proxy config.
+  virtual void OnProxyConfigChanged(ProxyPrefs::ConfigState config_state,
+                                    const net::ProxyConfig& config);
+
+  // NotificationObserver implementation:
+  virtual void Observe(int type,
+                       const NotificationSource& source,
+                       const NotificationDetails& details);
+
+  // Converts a ProxyConfigDictionary to net::ProxyConfig representation.
+  // Returns true if the data from in the dictionary is valid, false otherwise.
+  bool PrefConfigToNetConfig(const ProxyConfigDictionary& proxy_dict,
+                             net::ProxyConfig* config);
+
+  const PrefService* prefs() const { return pref_service_; }
+  const bool update_pending() const { return update_pending_; }
+
+ private:
+  // Creates a proxy configuration from proxy-related preferences. Configuration
+  // is stored in |config|, return value indicates whether the configuration is
+  // valid.
+  ProxyPrefs::ConfigState ReadPrefConfig(net::ProxyConfig* config);
+
+  // Tracks configuration state. |pref_config_| is valid only if |config_state_|
+  // is not CONFIG_UNSET.
+  ProxyPrefs::ConfigState config_state_;
+
+  // Configuration as defined by prefs.
+  net::ProxyConfig pref_config_;
+
+  PrefService* pref_service_;
+  ChromeProxyConfigService* chrome_proxy_config_service_;  // Weak ptr.
+  bool update_pending_;  // True if config has not been pushed to network stack.
+  scoped_ptr<PrefSetObserver> proxy_prefs_observer_;
+
+  DISALLOW_COPY_AND_ASSIGN(PrefProxyConfigTracker);
+};
+
+#endif  // CHROME_BROWSER_NET_PREF_PROXY_CONFIG_TRACKER_H_